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<h1 class="title">piecesmodel.cpp 示例文件</h1>
<span class="subtitle">itemviews/puzzle/piecesmodel.cpp</span>
<!-- $$$itemviews/puzzle/piecesmodel.cpp-description -->
<div class="descr"> <a name="details"></a>
<pre class="cpp">

  <span class="comment">/****************************************************************************
  **
  ** Copyright (C) 2016 The Qt Company Ltd.
  ** Contact: https://www.qt.io/licensing/
  **
  ** This file is part of the examples of the Qt Toolkit.
  **
  ** $QT_BEGIN_LICENSE:BSD$
  ** Commercial License Usage
  ** Licensees holding valid commercial Qt licenses may use this file in
  ** accordance with the commercial license agreement provided with the
  ** Software or, alternatively, in accordance with the terms contained in
  ** a written agreement between you and The Qt Company. For licensing terms
  ** and conditions see https://www.qt.io/terms-conditions. For further
  ** information use the contact form at https://www.qt.io/contact-us.
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  ** Alternatively, you may use this file under the terms of the BSD license
  ** as follows:
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  ** &quot;Redistribution and use in source and binary forms, with or without
  ** modification, are permitted provided that the following conditions are
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  ****************************************************************************/</span>

  <span class="preprocessor">#include &quot;piecesmodel.h&quot;</span>

  <span class="preprocessor">#include &lt;QIcon&gt;</span>
  <span class="preprocessor">#include &lt;QMimeData&gt;</span>
  <span class="preprocessor">#include &lt;QRandomGenerator&gt;</span>

  PiecesModel<span class="operator">::</span>PiecesModel(<span class="type">int</span> pieceSize<span class="operator">,</span> <span class="type"><a href="../qtcore/qobject.html">QObject</a></span> <span class="operator">*</span>parent)
      : <span class="type"><a href="../qtcore/qabstractlistmodel.html">QAbstractListModel</a></span>(parent)<span class="operator">,</span> m_PieceSize(pieceSize)
  {
  }

  <span class="type"><a href="../qtcore/qvariant.html">QVariant</a></span> PiecesModel<span class="operator">::</span>data(<span class="keyword">const</span> <span class="type"><a href="../qtcore/qmodelindex.html">QModelIndex</a></span> <span class="operator">&amp;</span>index<span class="operator">,</span> <span class="type">int</span> role) <span class="keyword">const</span>
  {
      <span class="keyword">if</span> (<span class="operator">!</span>index<span class="operator">.</span>isValid())
          <span class="keyword">return</span> <span class="type"><a href="../qtcore/qvariant.html">QVariant</a></span>();

      <span class="keyword">if</span> (role <span class="operator">=</span><span class="operator">=</span> <span class="type"><a href="../qtcore/qt.html">Qt</a></span><span class="operator">::</span>DecorationRole)
          <span class="keyword">return</span> <span class="type"><a href="../qtgui/qicon.html">QIcon</a></span>(pixmaps<span class="operator">.</span>value(index<span class="operator">.</span>row())<span class="operator">.</span>scaled(m_PieceSize<span class="operator">,</span> m_PieceSize<span class="operator">,</span>
                           <span class="type"><a href="../qtcore/qt.html">Qt</a></span><span class="operator">::</span>KeepAspectRatio<span class="operator">,</span> <span class="type"><a href="../qtcore/qt.html">Qt</a></span><span class="operator">::</span>SmoothTransformation));
      <span class="keyword">else</span> <span class="keyword">if</span> (role <span class="operator">=</span><span class="operator">=</span> <span class="type"><a href="../qtcore/qt.html">Qt</a></span><span class="operator">::</span>UserRole)
          <span class="keyword">return</span> pixmaps<span class="operator">.</span>value(index<span class="operator">.</span>row());
      <span class="keyword">else</span> <span class="keyword">if</span> (role <span class="operator">=</span><span class="operator">=</span> <span class="type"><a href="../qtcore/qt.html">Qt</a></span><span class="operator">::</span>UserRole <span class="operator">+</span> <span class="number">1</span>)
          <span class="keyword">return</span> locations<span class="operator">.</span>value(index<span class="operator">.</span>row());

      <span class="keyword">return</span> <span class="type"><a href="../qtcore/qvariant.html">QVariant</a></span>();
  }

  <span class="type">void</span> PiecesModel<span class="operator">::</span>addPiece(<span class="keyword">const</span> <span class="type"><a href="../qtgui/qpixmap.html">QPixmap</a></span> <span class="operator">&amp;</span>pixmap<span class="operator">,</span> <span class="keyword">const</span> <span class="type"><a href="../qtcore/qpoint.html">QPoint</a></span> <span class="operator">&amp;</span>location)
  {
      <span class="type">int</span> row;
      <span class="keyword">if</span> (<span class="type"><a href="../qtcore/qrandomgenerator.html">QRandomGenerator</a></span><span class="operator">::</span>global()<span class="operator">-</span><span class="operator">&gt;</span>bounded(<span class="number">2</span>) <span class="operator">=</span><span class="operator">=</span> <span class="number">1</span>)
          row <span class="operator">=</span> <span class="number">0</span>;
      <span class="keyword">else</span>
          row <span class="operator">=</span> pixmaps<span class="operator">.</span>size();

      beginInsertRows(<span class="type"><a href="../qtcore/qmodelindex.html">QModelIndex</a></span>()<span class="operator">,</span> row<span class="operator">,</span> row);
      pixmaps<span class="operator">.</span>insert(row<span class="operator">,</span> pixmap);
      locations<span class="operator">.</span>insert(row<span class="operator">,</span> location);
      endInsertRows();
  }

  <span class="type"><a href="../qtcore/qt.html">Qt</a></span><span class="operator">::</span>ItemFlags PiecesModel<span class="operator">::</span>flags(<span class="keyword">const</span> <span class="type"><a href="../qtcore/qmodelindex.html">QModelIndex</a></span> <span class="operator">&amp;</span>index) <span class="keyword">const</span>
  {
      <span class="keyword">if</span> (index<span class="operator">.</span>isValid())
          <span class="keyword">return</span> (<span class="type"><a href="../qtcore/qabstractlistmodel.html">QAbstractListModel</a></span><span class="operator">::</span>flags(index)<span class="operator">|</span><span class="type"><a href="../qtcore/qt.html">Qt</a></span><span class="operator">::</span>ItemIsDragEnabled);

      <span class="keyword">return</span> <span class="type"><a href="../qtcore/qt.html">Qt</a></span><span class="operator">::</span>ItemIsDropEnabled;
  }

  bool PiecesModel<span class="operator">::</span>removeRows(<span class="type">int</span> row<span class="operator">,</span> <span class="type">int</span> count<span class="operator">,</span> <span class="keyword">const</span> <span class="type"><a href="../qtcore/qmodelindex.html">QModelIndex</a></span> <span class="operator">&amp;</span>parent)
  {
      <span class="keyword">if</span> (parent<span class="operator">.</span>isValid())
          <span class="keyword">return</span> <span class="keyword">false</span>;

      <span class="keyword">if</span> (row <span class="operator">&gt;</span><span class="operator">=</span> pixmaps<span class="operator">.</span>size() <span class="operator">|</span><span class="operator">|</span> row <span class="operator">+</span> count <span class="operator">&lt;</span><span class="operator">=</span> <span class="number">0</span>)
          <span class="keyword">return</span> <span class="keyword">false</span>;

      <span class="type">int</span> beginRow <span class="operator">=</span> <a href="../qtcore/qtglobal.html#qMax">qMax</a>(<span class="number">0</span><span class="operator">,</span> row);
      <span class="type">int</span> endRow <span class="operator">=</span> <a href="../qtcore/qtglobal.html#qMin">qMin</a>(row <span class="operator">+</span> count <span class="operator">-</span> <span class="number">1</span><span class="operator">,</span> pixmaps<span class="operator">.</span>size() <span class="operator">-</span> <span class="number">1</span>);

      beginRemoveRows(parent<span class="operator">,</span> beginRow<span class="operator">,</span> endRow);

      <span class="keyword">while</span> (beginRow <span class="operator">&lt;</span><span class="operator">=</span> endRow) {
          pixmaps<span class="operator">.</span>removeAt(beginRow);
          locations<span class="operator">.</span>removeAt(beginRow);
          <span class="operator">+</span><span class="operator">+</span>beginRow;
      }

      endRemoveRows();
      <span class="keyword">return</span> <span class="keyword">true</span>;
  }

  <span class="type"><a href="../qtcore/qstringlist.html">QStringList</a></span> PiecesModel<span class="operator">::</span>mimeTypes() <span class="keyword">const</span>
  {
      <span class="type"><a href="../qtcore/qstringlist.html">QStringList</a></span> types;
      types <span class="operator">&lt;</span><span class="operator">&lt;</span> <span class="string">&quot;image/x-puzzle-piece&quot;</span>;
      <span class="keyword">return</span> types;
  }

  <span class="type"><a href="../qtcore/qmimedata.html">QMimeData</a></span> <span class="operator">*</span>PiecesModel<span class="operator">::</span>mimeData(<span class="keyword">const</span> <span class="type"><a href="../qtcore/qmodelindex.html#QModelIndexList-typedef">QModelIndexList</a></span> <span class="operator">&amp;</span>indexes) <span class="keyword">const</span>
  {
      <span class="type"><a href="../qtcore/qmimedata.html">QMimeData</a></span> <span class="operator">*</span>mimeData <span class="operator">=</span> <span class="keyword">new</span> <span class="type"><a href="../qtcore/qmimedata.html">QMimeData</a></span>();
      <span class="type"><a href="../qtcore/qbytearray.html">QByteArray</a></span> encodedData;

      <span class="type"><a href="../qtcore/qdatastream.html">QDataStream</a></span> stream(<span class="operator">&amp;</span>encodedData<span class="operator">,</span> <span class="type"><a href="../qtcore/qiodevice.html">QIODevice</a></span><span class="operator">::</span>WriteOnly);

      foreach (<span class="type"><a href="../qtcore/qmodelindex.html">QModelIndex</a></span> index<span class="operator">,</span> indexes) {
          <span class="keyword">if</span> (index<span class="operator">.</span>isValid()) {
              <span class="type"><a href="../qtgui/qpixmap.html">QPixmap</a></span> pixmap <span class="operator">=</span> qvariant_cast<span class="operator">&lt;</span><span class="type"><a href="../qtgui/qpixmap.html">QPixmap</a></span><span class="operator">&gt;</span>(data(index<span class="operator">,</span> <span class="type"><a href="../qtcore/qt.html">Qt</a></span><span class="operator">::</span>UserRole));
              <span class="type"><a href="../qtcore/qpoint.html">QPoint</a></span> location <span class="operator">=</span> data(index<span class="operator">,</span> <span class="type"><a href="../qtcore/qt.html">Qt</a></span><span class="operator">::</span>UserRole<span class="operator">+</span><span class="number">1</span>)<span class="operator">.</span>toPoint();
              stream <span class="operator">&lt;</span><span class="operator">&lt;</span> pixmap <span class="operator">&lt;</span><span class="operator">&lt;</span> location;
          }
      }

      mimeData<span class="operator">-</span><span class="operator">&gt;</span>setData(<span class="string">&quot;image/x-puzzle-piece&quot;</span><span class="operator">,</span> encodedData);
      <span class="keyword">return</span> mimeData;
  }

  bool PiecesModel<span class="operator">::</span>dropMimeData(<span class="keyword">const</span> <span class="type"><a href="../qtcore/qmimedata.html">QMimeData</a></span> <span class="operator">*</span>data<span class="operator">,</span> <span class="type"><a href="../qtcore/qt.html">Qt</a></span><span class="operator">::</span>DropAction action<span class="operator">,</span>
                                 <span class="type">int</span> row<span class="operator">,</span> <span class="type">int</span> column<span class="operator">,</span> <span class="keyword">const</span> <span class="type"><a href="../qtcore/qmodelindex.html">QModelIndex</a></span> <span class="operator">&amp;</span>parent)
  {
      <span class="keyword">if</span> (<span class="operator">!</span>data<span class="operator">-</span><span class="operator">&gt;</span>hasFormat(<span class="string">&quot;image/x-puzzle-piece&quot;</span>))
          <span class="keyword">return</span> <span class="keyword">false</span>;

      <span class="keyword">if</span> (action <span class="operator">=</span><span class="operator">=</span> <span class="type"><a href="../qtcore/qt.html">Qt</a></span><span class="operator">::</span>IgnoreAction)
          <span class="keyword">return</span> <span class="keyword">true</span>;

      <span class="keyword">if</span> (column <span class="operator">&gt;</span> <span class="number">0</span>)
          <span class="keyword">return</span> <span class="keyword">false</span>;

      <span class="type">int</span> endRow;

      <span class="keyword">if</span> (<span class="operator">!</span>parent<span class="operator">.</span>isValid()) {
          <span class="keyword">if</span> (row <span class="operator">&lt;</span> <span class="number">0</span>)
              endRow <span class="operator">=</span> pixmaps<span class="operator">.</span>size();
          <span class="keyword">else</span>
              endRow <span class="operator">=</span> <a href="../qtcore/qtglobal.html#qMin">qMin</a>(row<span class="operator">,</span> pixmaps<span class="operator">.</span>size());
      } <span class="keyword">else</span> {
          endRow <span class="operator">=</span> parent<span class="operator">.</span>row();
      }

      <span class="type"><a href="../qtcore/qbytearray.html">QByteArray</a></span> encodedData <span class="operator">=</span> data<span class="operator">-</span><span class="operator">&gt;</span>data(<span class="string">&quot;image/x-puzzle-piece&quot;</span>);
      <span class="type"><a href="../qtcore/qdatastream.html">QDataStream</a></span> stream(<span class="operator">&amp;</span>encodedData<span class="operator">,</span> <span class="type"><a href="../qtcore/qiodevice.html">QIODevice</a></span><span class="operator">::</span>ReadOnly);

      <span class="keyword">while</span> (<span class="operator">!</span>stream<span class="operator">.</span>atEnd()) {
          <span class="type"><a href="../qtgui/qpixmap.html">QPixmap</a></span> pixmap;
          <span class="type"><a href="../qtcore/qpoint.html">QPoint</a></span> location;
          stream <span class="operator">&gt;</span><span class="operator">&gt;</span> pixmap <span class="operator">&gt;</span><span class="operator">&gt;</span> location;

          beginInsertRows(<span class="type"><a href="../qtcore/qmodelindex.html">QModelIndex</a></span>()<span class="operator">,</span> endRow<span class="operator">,</span> endRow);
          pixmaps<span class="operator">.</span>insert(endRow<span class="operator">,</span> pixmap);
          locations<span class="operator">.</span>insert(endRow<span class="operator">,</span> location);
          endInsertRows();

          <span class="operator">+</span><span class="operator">+</span>endRow;
      }

      <span class="keyword">return</span> <span class="keyword">true</span>;
  }

  <span class="type">int</span> PiecesModel<span class="operator">::</span>rowCount(<span class="keyword">const</span> <span class="type"><a href="../qtcore/qmodelindex.html">QModelIndex</a></span> <span class="operator">&amp;</span>parent) <span class="keyword">const</span>
  {
      <span class="keyword">if</span> (parent<span class="operator">.</span>isValid())
          <span class="keyword">return</span> <span class="number">0</span>;
      <span class="keyword">else</span>
          <span class="keyword">return</span> pixmaps<span class="operator">.</span>size();
  }

  <span class="type"><a href="../qtcore/qt.html">Qt</a></span><span class="operator">::</span>DropActions PiecesModel<span class="operator">::</span>supportedDropActions() <span class="keyword">const</span>
  {
      <span class="keyword">return</span> <span class="type"><a href="../qtcore/qt.html">Qt</a></span><span class="operator">::</span>CopyAction <span class="operator">|</span> <span class="type"><a href="../qtcore/qt.html">Qt</a></span><span class="operator">::</span>MoveAction;
  }

  <span class="type">void</span> PiecesModel<span class="operator">::</span>addPieces(<span class="keyword">const</span> <span class="type"><a href="../qtgui/qpixmap.html">QPixmap</a></span><span class="operator">&amp;</span> pixmap)
  {
      <span class="keyword">if</span> (<span class="operator">!</span>pixmaps<span class="operator">.</span>isEmpty()) {
          beginRemoveRows(<span class="type"><a href="../qtcore/qmodelindex.html">QModelIndex</a></span>()<span class="operator">,</span> <span class="number">0</span><span class="operator">,</span> pixmaps<span class="operator">.</span>size() <span class="operator">-</span> <span class="number">1</span>);
          pixmaps<span class="operator">.</span>clear();
          locations<span class="operator">.</span>clear();
          endRemoveRows();
      }
      <span class="keyword">for</span> (<span class="type">int</span> y <span class="operator">=</span> <span class="number">0</span>; y <span class="operator">&lt;</span> <span class="number">5</span>; <span class="operator">+</span><span class="operator">+</span>y) {
          <span class="keyword">for</span> (<span class="type">int</span> x <span class="operator">=</span> <span class="number">0</span>; x <span class="operator">&lt;</span> <span class="number">5</span>; <span class="operator">+</span><span class="operator">+</span>x) {
              <span class="type"><a href="../qtgui/qpixmap.html">QPixmap</a></span> pieceImage <span class="operator">=</span> pixmap<span class="operator">.</span>copy(x<span class="operator">*</span>m_PieceSize<span class="operator">,</span> y<span class="operator">*</span>m_PieceSize<span class="operator">,</span> m_PieceSize<span class="operator">,</span> m_PieceSize);
              addPiece(pieceImage<span class="operator">,</span> <span class="type"><a href="../qtcore/qpoint.html">QPoint</a></span>(x<span class="operator">,</span> y));
          }
      }
  }

</pre>
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<!-- @@@itemviews/puzzle/piecesmodel.cpp -->
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